Drafting device



Dec. 31, 1968 E. BOK 3,419,335

DRAFTING DEVICE Filed Jan. 12, 1968 Sheet I I! Hill-"W F/ INVMOR AITORNEY Dec. 31, 1968 v 5, 30 3,419,335

DRAFTING DEVICE Filed Jan. 12, 1968 I i WW "w INVENT OR [aw/Pu 50% Dec. 31, 1968 E. BOK 3,419,335

DRAFTING msvzcn Filed Jan. 12, 1968 Sheet a 01 4 INVENTOR [DA ii 54% ATTORNEY Dec. 31 1968 E. BOK 3,419,335

DRAFTING DEVICE Filed Jan. 12, 1968 ATTORNEY United States Patent 3,419,335 DRAFTING DEVICE Edward Bok Falls Church, Va., assignor to Dike, Inc., Washington, D.C., a corporation of the District of Columbia Filed Jan. 12, 1968, Ser. No. 697,433 8 Claims. (Cl. 40148) ABSTRACT OF THE DISCLOSURE A drafting pen or drawing instrument of the type embodying holder, an ink reservoir supported in the holder and a drafting pen tip communicating with the reservoir and extending outwardly of the holder. Structural innovations include a support pin supported co-extensively with the drafting pen and enabling a pivoting of the entire assembly independently of the pen tip.

Background of the invention Field of the invention-Present drafting devices for drawing ink lines, also in free hand work, consist mainly of a holder, an ink reservoir supported in the holder and tubular pen tip with axial needle communicating with the reservoir and extending outwardly of the holder.

In drafting lines with such a conventional drafting pen, which is held by hand and with the drafting pen tip resting upon the drawing sheet, the position of the drafting pen has to be held approximately perpendicular to the surface of the drawing sheet.

To achieve good ink lines the draftsman has to apply manual pressure upon the drafting pen tip to achieve satisfactory contact of the tip with the drawing sheet. Otherwise and without such pressure on the pen tip, trembling tensions in the draftsmans hand, which cannot be avoided, will spill the ink lines by transferring these trembling tensions over to drawn line, as illustrated in FIG. 4. On the other hand if too much pressure is applied to the pen tip, the ink flow will become inadequate, resulting in an irregular ink line, having some non-ink covered areas, especially near the edges of the line because of this poor ink flow.

In the necessary perpendicular positioning of the drafting pen with respect to the hand, the hand rests with its palm, little finger and ring finger bearing upon the drawing sheet. Thus, the turning or pivoting of the hand around the palm in drafting free hand lines results in shocking movements of the pen over the drawing sheet due to frictional forces, as the little finger and ring finger also turn or pivot over the drawing sheet. The shocking movements are noticeable in the drawn ink line. Further, the unnatural perpendicular position of the drafting pen induces fatigue and extra trembling forces in the hand and the consequent unwanted extra movements of the inking pen.

Furthermore, in free hand drafting with such conventional pens, many repositioning movements of the hand on the drawing sheet are necessary, due to the short distance between the draftsmans palm and the ink pen. As a result, there are necessarily many stand-still pivotings of the inking pen tip on the sheet and liftings of this pen tip from the sheet. Since perpendicular positioning of the drafting pen limits usability, these stand-still pivoting and liftings of the inking pen result in many irregularities in the drawn line.

The overall result, especially in free hand work, is poor quality of ink line drawings.

Description of the prior art.-The prior art has suggested the use of pivoting supports or guides in combina- Patented Dec. 31, 1968 tion with drafting pencils or pens. However, none of the prior art devices were constructed so that the pivoting support took the full weight of the artists hand, while the drafting pen tip was independently urged outwardly of the holder by an adjustable compression spring. None of the prior art devices taught means for locking the drafting pen tip in various attitudes of longitudinal extension with respect to the pen holder.

Faust (945,026) and Mingos (1,818,081) are typical of guides used with drafting pencils. Dentzler (2,362,992) tripod device is used for holding a drafting pen.

Civitarese (3,179,089) is a pivoting assembly used principally to rotate the drafting pen itself, so as to avoid abrasion. There is no suggestion or capability of locking the pen tip in various attitudes of longitudinal extension and there is no capability of varying the spring pressure in the pen tip.

Summary of the invention The drafting pen according to the present invention includes a support or guide pin, coextensively positioned with respect to the drafting pen tip, as an independent bearing supporting surface movable with the pen tip over the drawing sheet or tool.

In connection with a tubular inking pen with a small outside diameter, the guide pin can be a straight pin, whereas in connection with an inking pen with a medium or large outside diameter the guide pin can be furnished with a rotatable ball-bearing at its lower end.

In order to achieve constant prefixed pressure on the drafting pen tip, the present drafting pen device mainly consists of a holder which is held by the hand, a tubular writing tip and a guide pin co-extending from the holder, so that the guide pin directly transmits the force of the hand on the holder to the drawing sheet. The holder contains an ink reservoir cartridge communication with the pen tip which is movable up and down in this holder so as to vary the degree of longitudinal extensibility of the pen tip with respect to the holder and adjacent guide pin.

In drawing lines with the device the inking pen only presses with the weight of the ink cartridge bearing upon the sheet, resulting in an even perpendicular force of the inking pen tip upon the approximately horizontally positioned sheet. Conventionally, the entire weight of the artists hand, as much as 100 grams, bears, directly upon the writing pen tip.

To enable drafting lines with variant pressure on the drafting pen tip, the holder is also furnished with a compression spring which can be positioned between an adjustable screw knob seated in the top of the holder and the ink cartridge or reservoir. The compression spring produces an adjustable force on the ink cartridge or reservoir and inking pen tip in the direction of the axis of the drafting pen.

The support or guide pin is mounted in the holder so as to be supported coextensively during drafting behind the pen tip and intermediate the pen tip and the palm of the draftsmans hand.

If the conventional drafting device is held in an approximately perpendicular position to the surface of the drawing sheet, an easy movement of the inking pen over the sheet surface is maintained. The perpendicular sup port of the drafting device, however, is unnatural.

The present drafting pen therefore is made to be held in a. natural inclined position by hand and the elevation between the axis of the device and the surface of the drawing sheet is approximately 60 instead of with the bottom part of the inking pen tip being the greatest distance from the palm of the draftsman. Similarly, the elevation between the main surfaces of both inking pen tip and guide pin, if no ball bearing is used, and the drawing surface or sheet is also approximately 60.

Furthermore, the bottom part of the inking pen tip is profiled in such a manner that the surface, that slides over the drawing sheet, has an approximately circular form.

An improved embodiment of the present drafting pen is provided with a knob adjuster as part of the ink cartridge and which knob is brought through a slot in the side Wall of the holder. The profile of the slot is such that two radial positions of the knob adjuster are obtained with approximately 90 radial clearance in between these positions. Drafting with the knob in a first position results in simultaneous touching of the drawing sheet with both inking pen tip and support pin. Whereas drafting with the knob in a second position results in a touching of only the inking pen tip over the drawing sheet, the guide pin being free from the sheet. In this second position of the knob the drafting pen tip can be used in lettering or handwriting. Since the longitudinal extension of the support pin is fixed, the support pin in this second position can move over an elevated surface of ruler or curved drafting tool placed upon the drawing sheet.

Furthermore, the slot in which the knob moves from first to second position is profiled in such a way, that in both positions the knob can move upwards and downwards axially of the holder, enabling for the first radial position and the second radial position three longitudinal positions of the knob in the direction of the axis of the inking pen. By means of this adjuster knob all drafting and writing conditions can be covered with the device including, for instance, lifting of either inking pen tip or support pin from the drawing sheet. Also, circumferential access to the inking pen tip enables a thorough cleaning of the pen tip.

By supporting an inking needle holder inside the drafting pen holder so the inking needle extends axially of the inking pen tip, a fixed axial position of the needle with respect to the circumference of the tubular inking pen tip is achieved.

Also, the bottom of this needle can be profiled or cut for example at 60 to produce the easiest movement of the needle over the surface of the drawing sheet under the weight of the needle holder or by means of an adjustable compression spring interposed between the needle holder and the top of an ink cartridge which houses the needle holder and reservoir.

Brief description of the drawings FIG. 1 is a perspective view of a drafting pen according to the present invention, which is held by the right hand in an inclined position and produces a curved drafting line;

FIG. 2 is a perspective view of a conventional drafting pen which is held by the right hand in a non-natural yet necessary perpendicular position in order to produce a curved drafting line;

FIG. 3 is a side view of the bottom part of the conventional drafting device according to FIG. 2, whereby the inclined or non-perpendicular position of this drafting pen with respect to the drafting surface results in the resting upon the drafting surface of only a small part of the pen tip bottom and, as is indicated in FIG. 4, an irregular or wavy inkline is obtained;

'FIG. 5 is a side view of the drafting device in a 60 elevation with its support pin and ink pen co-extending to rest upon the drawing sheet;

FIG. 6 is a transverse section of drafting device 10 as in FIG. 5;

FIG. 7 is an enlarged transverse section of the ink cartridge of the drafting device according to FIGS. 5 and 6;

FIG. 8, enlarged to 1, is a transverse fragmentary section of the bottom part of the drafting device 10 wherein its inking pen tip and guide pin have a small outside diameter;

FIG. 9, enlarged 15 to 1, is a bottom fragmentary view of the drafting device 10 according to FIG. 8;

FIG. 10, enlarged 15 to l, is a transverse section of the bottom part of a modified drafting device 10 wherein the inking pen tip and guide pin have a medium outside diameter;

FIG. 11 is an enlarged fragmentary side elevational view of the drafting device 10 according to FIG. 5, showing a knob 34 for changing the position of the inking pen tip relatively to that of the guide pin, which knob 34 extending through a slot in the side wall of the holder;

FIG. 12 is a horizontal section of the knob construction according to FIG. 11, showing knob 34 in that part of the slot of the holder whereby the drafting device 10 is suitable for freehand drafting or writing, inking pen tip 16 being substantially co-extensive with support pin 14;

FIGS. 13, 14 and 15 are enlarged fragmentary side views of the drafting device showing three different longitudinal positions of the inking pen tip relative to that of the guide pin, according to three different longitudinal positions of the knob in its radial position as is indicated in FIGS. 11 and 12;

FIG. 16 is a cross-section of the knob construction according to FIG. 11 showing knob 34 in that part of the slot of the holder, whereby the drafting device 10 is most suitable for producing ink lines with the aid of a ruler or curved drafting tool as is illustrated in FIG. 17 in a fragmentary side view of the drafting device, inking pen tip 16 being internally pivoted to one side and longitudinally extensional with respect to support pin 14; and

FIGS. 18, 19 and 20 are enlarged fragmentary side views of the drafting device, showing three different longitudinal positions of inking pen tip 16 relative to that of the guide pin 14, according to three longitudinal positions of the knob in its radial position as is indicated in FIG.

16, combined with a ruler which is indicated with a dash point line.

Description of the preferred embodiments In FIG. 1 a drafting device according to the invention and generally designated as 10 is illustrated as being held in a natural, inclined position by hand 12, whereby guide pin 14 and inking pen tip 16 rest simultaneously upon the drawing sheet 18, enabling free hand production of solid, curved line 19 without noticeable deformation. The draftsmans hand 12 rests with only its palm 20 upon the sheet 18 and the force, which is applied to the drafting device 10 by hand 12 is mainly transferred by guide or support pin 14 to the drafting surface 18. The axial force thrust upon the inking pen tip 16 in the direction of the drawing sheet 18 is thereby comparatively small and constant during the drafting, resulting in an even flow of ink from a reservoir in holder 22 through the inking pen tip 16 to sheet 18. Also, inking pen tip 16 does not damage sheet 18 due to any excessive force in this pen.

As the guide pin 14 moves easily over the sheet 18, the distance between it and palm 20 is 3-4 inches. By turning or pivoting the hand and drafting device around hand palm 20, combined with stretching or contracting the thumb, fore and middle fingers, one can achieve good free hand drafting over a distance of approximately four inches without interruption or lifting of the inking pen tip from the drafting surface.

In FIG. 2 a conventional drafting device 24 is illustrated as being held conventionally yet in an unnatural perpendicular position to the surface of the drawing sheet 18, whereby only its inking pen tip 26 rests upon this drawing sheet, with the consequent free hand production of irregular or wavy curved line 19'. In this conventional position the drafsmans hand rests with palm A, surface B of the little finger and surface C of the ring finger upon sheet 18, with the result that turning or pivoting of the hand around the hand palm A gives a shocking movement of the drafting device 24 due to frictional forces, as surfaces B and C of the hand also move over the drawing sheet. Additionally, the unnatural perpendicular position of the drafting device results in fatigue and extra trembling forces in the hand which are transmitted as unwanted extra movements to the drafting device.

The drafting pen tip 26 has to carry the whole force of the hand bearing upon the drafting device 24. The precise perpendicular position of the pen tip 2 6 with respect to the drawing sheet 18 cannot be maintained with the result that, as illustrated in FIGS. 3 and 4, bottompoints A and A of this tip 26, which determine the full width of the drafted line, are removed from the drawing sheet and only the bottompoint B of the ink pen tip 26 is resting upon the drawing sheet. The result is the irregular linkline 19', having a variant and a smaller width, as is illustrated in FIG. 4; also, there is additional damage of the drawing sheet 18 due to too heavy forces on the drafting device 24, which are transmitted through bottompoint B to the drawing sheet and induce a scraping of the drafting paper with the pen tip 26.

The total result of the free hand inking with drafting device 24 can be easily noticed in the poor inkline 19, illustrated in FIG. 2, as well as FIG. 4.

Furthermore, the actual distance between conventional inking pen tip 26 at point D and the combination of surfaces A, B and C of the hand 12 is only approximately one inch with result that only free hand drafting over a distance of approximately one inch without interruption lifting can be obtained. This interruption induces extra line width deformations because of the difficulty in placing the ink pen 26 exactly on the end of the drawn line.

The present drafting pen is illustrated also again in FIGS. 5 and 6.

Drafting device 10 thereby consists principally of holder 22 with upper extension 28 screwed on it, guide or support pin 14 anchored in holder bottom 30, and ink cartridge 32, see also FIG. 7, with inking pen 16 brought through opening 48 of holder bottom 30 and knob 34 brought through opening 36 in holder 22. A compres sion spring construction 38 in the holder extension 28 provides an adjustable downward force on the ink cartridge 32. Ink cartridge 32 includes housing 40, which can be a plastic molding and also serves as an ink reservoir, and the screw cap 42 screwed in the bottom of housing 40 as a. closure for the ink.

The outside diameter of the housing 40 is small compared to the inside diameter of the conical inside 44 of holder 22, enabling longitudinal moving of ink cartridge 32 to its downward position and by moving laterally the top screw cap 42 of the cartridge to one side by means of cartridge knob 34 extending through the opening 36.

The lock pin 46, longitudinally movable in the holder 22 and resting on the screw cap 42, thereby supports or locks the top part of cartridge 32 in the eccentric position illustrated in FIG. 6. Lock pin 46 also serves as a second guidance for cartridge 32 so that the transverse positioning of the ink cartridge 34 with respect to the holder is secured without affecting the capability of opening 48 in holder bottom 30 serving as a preliminary guidance for the inking pen tip 26.

Seat 49 rests under tension of compression spring 50 upon the lockpin 46, whereby the force of spring 50 upon seat 49 is adjustable by means of the screw knob 52, which may be threadedly screwed in holder extension 28. As a result, an adjustable downward force on the inking pen tip 16 is obtained, which force during drafting is constant.

The combination of screw knob "52, lock pin 46, the inside wall 47 of holder 22 and the force of compression spring 50 provide a moving of the ink cartridge 40 only by moving the knob 34, preventing an unwanted turning of the inking pen 16 in the holder 22.

In FIG. 8 the holder bottom 30 is shown in a transverse section with inking pen 16' of a small size diameter and the guide pin 14', having approximately the same diameter, anchored in the bottom 30 adjacent to this inking pen.

The surface of the ends 54 and 56 respectively of guide pin 14' and inking pen tip 16' are cut or profiled at approximately 60 elevation to their axis, enabling a good surface to surface position of the inking pen tip 16' and guide pin 14 with respect to the drawing sheet 1 8. The entire inking device 10, as illustrated in FIG. 1, is held by hand under approximately 60 elevation to the surface of sheet 18.

To achieve a maximum guidance of inking pen tip 16' holder bottom 30 and conical tip 58 are extended longitudinally.

In the ink cartridge 32, as illustrated in FIG. 7, needle holder 33 is placed so that attached needle is fed through the hollow inking pen tip 16. With the aid of the profiled inner wall 37 of housing the needle holder 33 is locked against turning, so that needle 35 can be maintained axially equidistant from the circumference of tubular inking pen 16.

Needle holder 33 has such a weight, that by a shocking or jerking up and down of holder 22, needle holder 33 and with it the needle 35 can react against the force of the very light compression spring 39 so that an ink flow in the inking pen 16 can be produced.

With the aid of the ball 41, which under pressure of the compression spring 43 rests against the seat 45, an ideal sealing of the top of the ink cartridge 32 is achieved. By the shocking or jerking up and down movement of holder 22, ball 41 can be removed from seat and a vacuum under pressure in the ink cartridge 32 due to the usage of ink by drafting can be eliminated. Thus, shocking or jerking movement of holder 22 effects good ink flow.

As illustrated in FIG. 6, conical extension 58 has a small width and can also serve as a guidance to lead the drafting device 10' along a ruler or other drafting tool.

In FIG. 10 the holder bottom 30 is shown in a transverse section with the inking pen 16" of a medium or large diameter and whereby the guide pin 14" is anchored in bottom 30" at some distance from the inking pen 16" so as to eliminate the possibility under normal drafting conditions of pin 14 touching the inked line produced by pen tip 16". A ball 60 may 'be rotatably supported in recess 62 by means of flange on tip 64.

In FIGS. 11 and 12 the cartridge knob 34 is shown as being locked in a first radial direction in end 60 of slot 36, whereby it can move upward to notch 62 or downward to notch 72. The longitudinal position of the cartridge 32 with respect to the holder and as a result the longitudinal position of the inking pen tip 16 to the guide pin 14, thereby depends upon the lateral and longitudinal position of knob 34.

In FIGS. 5 and 6 cartridge knob 34 is radially positioned as shown in FIGS. 11, 12 and 14. As the guide pin 14 rests upon the drawing sheet 18 also the inking pen tip 16 rests upon this sheet under the weight of the ink cartridge 32 and the force of the compression spring 50.

By moving the knob upwards to the lock-end notch 62 with the aid of the forefinger inking pen tip 16 is lifted from the drawing sheet 18, as illustrated in FIG. 13.

This lifting of the inking pen tip 16 is a means to enable an exact ending of the ink line 70, especially with free hand drafting, whereby after the lifting of the ink pen tip 16, guide pin 14 remains resting upon the sheet 18 as a pivot for the draftsmans hand 12. As hand 12 pivots upon guide pin 14, and both hand 12 and drafting device 10 have achieved new position, inking pen tip 16 may be re-lowered to the sheet 18 to rest upon the end of the previously drawn ink line as is illustrated in FIG. 14.

A condition in free hand drafting is possible, in which the guide pin 14 has to be removed from the drawing sheet 18. This position, illustrated in FIG. 15, is achieved by reducing the downward force of the hand on the drafting device 10 to a value that is smaller than that of the compression spring 50, resulting in an automatic lifting of holder 22 with respect to guide pin 14 and the drawing sheet. Profile cut 65, see also FIG. 10, which is adjacent to the end 54 of the inking pen 16" provides a circular shape of this pin end, which, as is indicated, rests upon the drawing sheet 18.

In FIG. 16 the cartridge knob 34 is shown as this knob is locked in the second position in the part 74 of slot 36, whereby knob 34 can move up and downward in this slot part 74 to the respective notches 76 and 78. The normal drafting position for the drafting device is thereby indicated in the FIG. 19, whereby knob 34 is in its midportion and as the inking pen tip 16 rests upon the drawing sheet 18, the guide pin 14 rests upon ruler 80, which is placed on sheet 18. By moving the knob 34 upwards to the notch 76, the position according to the FIG. 18 is obtained for the drafting device 10.

By moving the knob 34 downwards against the lock end 78, the position according to FIG. 20 is obtained for the drafting device 10 with the guide pin 14 being removed from ruler 80.

The second position of knob 34 is illustrated in FIG. 16 and is achieved by turning the knob 90 from the position indicated in FIG. 12. With knob 34 in the FIG. 16 position, guide pin 14 at the side of the inking pen 16 is moving over the ruler 80, as indicated in the FIG. 17, still the normal 60 inclined position of the drafting device 10 can be maintained.

The knob position according to FIG. 16 is, because of the lifting of the guide pin 14 from the drawing sheet 18, very useful for hand writing with the drafting device 10.

I claim:

1. A drafting pen comprising:

(A) a holder;

(B) an ink reservoir supported in said holder;

(C) a drafting pen tip communicating with said reservoir, said drafting pen tip and an axial needle extending outwardly from said holder;

(D) a support means extending from said holder adjacent said drafting pen tip; and

(E) lock means movably supported in said holder and engaging said reservoir, so as to fix said drafting pen tip in various attitudes of longitudinal and lateral extension With respect to said holder;

(F) adjustable compression spring means supported between the interior of the holder and the reservoir,

8 so as to urge the drafting pen tip outwardly of the holder. 7

2. A drafting pen as in claim 1, said support means including a movable valve seated in said holder intermediate said reservoir and ambient pressure exteriorly of said holder, said valve being operable to eliminate vacuum conditions in said reservoir.

3. A drafting pen as in claim 2, said drafting pen tip being tubular, cut on a bias and chamfered, so as to present a circular cross section upon said drawing surface, notwithstanding inclined positioning of said holder and tip with respect to the drawing surface.

4. A drafting pen as in claim 3, said adjustable compression spring abutting said reservoir at its lower end and abutting at its upper end an adjusting knob threadedly mounted in said holder as a measure of the desired pressure of the pen tip upon the drawing surface independently of pressure exerted upon said support.

5. A drafting pen as in claim 4, wherein said support and pen tip are co-extensive with respect to said holder.

6. A drafting pen as in claim 5, wherein said pen tip extends longitudinally beyond said support and said support means is presented for bearing upon a surface above the drawing surface.

7. A drafting pen as in claim 4, wherein said reservoir is pivotable laterally within said suport means, so as to lockably guide said drafting pen tip in a plurality of modes of longitudinal extension with respect to said support means.

8. A drafting pen as in claim 7, said reservoir including a locking protuberance extending laterally through a side portion of said holder configured as a locking guide.

References Cited UNITED STATES PATENTS 1,409,037 3/1922 Starkey et al 401-260 1,568,347 1/1926 Shaw 40148 1,937,660 12/1933 Luker 40 1-259 2,855,897 10/1958 Benkowski 401258 X 3,247,828 4/1966 Basham 401260 X 3,332,108 7/1967 Bustamante 401-264 X LAWRENCE CHARLES, Primary Examiner.

US. Cl. X.R. 40l-260 

